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Hi Roger,
I'm interested to see your results from the OSC as I've been experimenting with a Trius-C SX694. I too see a greenish fringe on stars even when the colour balance looks OK on the main object.
I wonder if it might have anything to do with the Bayer matrix where there are two greens for each R/B in the array of 4 pix? I know in CCDStack there is an option to use only one of the 2 greens when Debayering. I've not experimented enough with it to see if it might make a difference.
The other issue I'm curious about is your method of extracting the RGB frames. In CCDStack there is the choice that needs to be made to extract to half resolution, or to interpolate to full frame. Adam Block recommends to go the half size route however I found with my data that I did not get nearly as good a result compared to interpolating immediately to full frame.
Finally, I was surprised to see that you used relatively short subframe times. With my Trius mono camera 5 min is about all I can do before LP steps in too heavily. When I shot NGC253 with the Trius-C I went up to 12-15 minutes based on Terry Platt's recommendation. I found that these much longer times gave a better result on the colour camera given the reduced sensitivity of the CCD due to the matrix and the lower inherent resolution. I used the Trius-c colour data and combined it with hi resolution luminance. I'm pretty happy with the effort. The picture is posted on these pages recently.
Peter
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